The Sysadmin’s Daily Grind: Cancerbero

RATTLING PORTS

When ports on a host start opening and closing like window shutters in a gale, it’s time for admins to pay attention.

Last month, I took a look at some features of the new Nmap 4.00. This topic is far too interesting for just one month, however, so this month, I’ll describe Cancerbero [1], a server monitoring tool based on Nmap. The tool, which was written in Perl, leverages the power of Nmap to port scan your network devices. Cancerbero logs the results in a database and uses a small-footprint PHP front-end to make the results more readable. The benefits are obvious: I get an at-a-glance overview of open ports, and I can easily see which ports are open or closed.

While going about his normal duties, Linux Magazine author Charly Kühnast was hit with a mean attack. Charly’s separate anti-spam server, which sits in front of his mail server, saved him from the mail storm.